Channel switching circuit and stimulator

Abstract

The utility model provides a channel switching circuit and a stimulator, the channel switching circuit comprises a high potential end, a low potential end, a forward current module, a reverse current module and an energy storage device, the forward current module comprises a first forward switch assembly and a second forward switch assembly, and at least one of the first forward switch assembly and the second forward switch assembly comprises a one-way conduction unit; the reverse current module comprises a first reverse switch assembly and a second reverse switch assembly, and at least one of the first reverse switch assembly and the second reverse switch assembly comprises a one-way conduction unit; the conduction direction of the one-way conduction unit is from the high potential end to the low potential end, so that the parasitic current can be blocked, and the safety of the stimulator is further improved. On the other hand, the utility model further provides the stimulator, the channel switching part in the stimulator is the channel switching circuit, and due to the fact that the parasitic current of the stimulator is blocked, mistaken stimulation electric signals cannot be formed, and the stimulator has high safety.

Description

Technical Field

[0001] This application belongs to the technical field of medical devices, and relates to a channel switching circuit of a stimulator, in particular to a channel switching circuit and a stimulator. Background Art

[0002] An electrical pulse stimulator is a medical device that emits electrical stimulation to human tissues through electrodes implanted in the human body for treatment. The electrical pulse stimulator generates different electrical stimulations to human tissues through a channel switching circuit.

[0003] However, since an alternating magnetic field is generated during magnetic resonance imaging (MRI) examination, an induced voltage is generated in the electrode wire of the channel switching circuit, forming a parasitic current in the channel switching circuit, and further generating a false stimulation electrical signal on human tissues, which affects the operation of the device and the safety of patients. In the prior art, generally, the electrical pulse stimulator is set to a specific working mode to avoid generating a false stimulation current, but this method is not convenient enough and is not friendly enough to patients.

[0004] Therefore, how to avoid the generation of parasitic current in the stimulator during MRI examination is an urgent problem to be solved by those skilled in the art. Summary of the Utility Model

[0005] The purpose of this application is to provide a channel switching circuit and a stimulator, which are used to solve the problem in the prior art that the alternating magnetic field generated during MRI examination of the receptor causes an induced voltage in the electrode wire of the channel switching circuit in the stimulator, and further generates a false stimulation electrical signal, causing a potential safety hazard.

[0006] In a first aspect, this application provides a channel switching circuit, including: a high potential terminal, a low potential terminal, a forward current module, a reverse current module, and an energy storage device connected between the high potential and the low potential. An external output load is connected to the channel switching circuit to form a current loop;

[0007] The forward current module and the external output load form a forward current path between the high potential terminal and the low potential terminal, and the reverse current module and the external output load form a reverse current path between the high potential terminal and the low potential terminal;

[0008] The forward current module includes a first forward switch component and a second forward switch component. The first forward switch component, the external output load, and the second forward switch component are connected in sequence, and at least one of the first forward switch component and the second forward switch component includes a unidirectional conduction unit;

[0009] The reverse current module includes a first reverse switch component and a second reverse switch component. The first reverse switch component, the external output load, and the second reverse switch component are connected in sequence. At least one of the first reverse switch component and the second reverse switch component includes a unidirectional conduction unit;

[0010] The conduction direction of the unidirectional conduction unit is from the high potential end to the low potential end.

[0011] In this application, by setting a unidirectional conduction unit in the channel switching circuit, the forward current path and the reverse current path during normal operation can be conducted as needed. When the stimulator is in a power-off state, since the unidirectional conduction unit blocks the current generated by the induced voltage at the electrode wire, any possible parasitic current is blocked, ensuring the safety of the stimulator and improving the usage effect of the patient.

[0012] In an embodiment of the present invention, the unidirectional conduction unit includes two MOS transistors connected back-to-back and a protection resistor;

[0013] One end of the protection resistor is connected to the source electrode of the MOS transistor, and the other end of the protection resistor is connected to the gate electrode of the MOS transistor.

[0014] In an embodiment of the present invention, the unidirectional conduction unit includes a MOS transistor and a diode, and the diode is connected to the source or drain electrode of the MOS transistor.

[0015] In an embodiment of the present invention, the unidirectional conduction unit includes a triode.

[0016] In an embodiment of the present invention, at least one of the first forward switch component and the second forward switch component includes a MOS transistor; at least one of the first reverse switch component and the second reverse switch component includes a MOS transistor. Since the impedance of the MOS transistor is higher than that of the triode, the generated current signal quality is higher. By setting two triodes and two MOS transistors in the channel switching circuit, it is possible to avoid the generation of false stimulation electrical signals by the stimulator while ensuring better signal quality and improving the usage effect of the stimulator.

[0017] In an embodiment of the present invention, the unidirectional conduction unit includes a MOS transistor and a leakage prevention resistor, and both ends of the leakage prevention resistor are respectively connected to the source electrode and the substrate of the MOS transistor.

[0018] In an embodiment of the present invention, the channel switching circuit further includes two DC blocking capacitors respectively located on both sides of the external output load, which are used to isolate the parasitic DC bias, avoid the human body polarization effect, and improve the safety of the stimulator.

[0019] In an embodiment of the present utility model, the channel switching circuit further includes a constant current output control module. One end of the constant current output control module is connected to the low potential end, and the other end of the constant current output control module is connected to the output ends of the second forward switch component and the second reverse switch component. The constant current control module is used to stabilize the current intensity of the channel switching circuit, and further stabilize the intensities of the forward current stimulation signal and the reverse current stimulation signal, so that the stimulator achieves a better use effect.

[0020] In an embodiment of the present utility model, the low potential end is a ground end.

[0021] In a second aspect, the present application provides a stimulator, including a stimulator body with a channel switching part and the channel switching circuit of the stimulator as described above. The channel switching circuit of the stimulator is connected in the stimulator body, and the stimulator is used to generate electrical stimulation to a human body structure as an output load.

[0022] Through the channel switching circuit capable of blocking parasitic current, the present application enables the stimulator to be compatible with magnetic resonance imaging (MRI) examination in a fully powered-off state without setting a specific working mode. While ensuring the safety of the stimulator, the operation is convenient and simple, and the device structure is simple with low cost, achieving a better use effect.

[0023] As described above, the present application provides a channel switching circuit and a stimulator. By means of a unidirectional conduction unit with a conduction direction from the high potential end to the low potential end, the parasitic current in the powered-off state of the stimulator is blocked, and at least one of the first forward switch component and the second forward switch component includes a unidirectional conduction unit, and at least one of the first reverse switch component and the second reverse switch component includes a unidirectional conduction unit to block all current loops that may generate parasitic current, so as to ensure that the stimulator will not generate false stimulation electrical signals and further improve the safety of the stimulator. At the same time, due to the simple structure and low cost of the unidirectional conduction unit adopted in the present application, it is beneficial to the practical application of the stimulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It shows a schematic structural diagram of a channel switching circuit according to an embodiment of the present application.

[0025] Figure 2 It shows a schematic structural diagram of a channel switching circuit according to an embodiment of the present application.

[0026] Figure 3 It shows a schematic structural diagram of another channel switching circuit according to an embodiment of the present application.

[0027] Figure 4 It shows a schematic structural diagram of yet another channel switching circuit according to an embodiment of the present application.

[0028] Figure 5 It shows a schematic diagram of a MOS transistor structure according to an embodiment of the present application.

[0029] Figure 6 It shows another equivalent schematic diagram of a channel switching circuit according to an embodiment of the present application.

[0030] Description of component labels

[0031] 100 Channel switching circuit

[0032] 101 Source

[0033] 102 Drain

[0034] 103 Gate

[0035] 104 Substrate

[0036] 111 First forward switch component

[0037] 112 Second forward switch component

[0038] 113 First reverse switch component

[0039] 114 Second reverse switch component

[0040] 115 External output load

[0041] R6 Leakage prevention resistor

[0042] Q10 First MOS transistor

[0043] Q11 Second MOS transistor

[0044] Q12 Third MOS transistor

[0045] Q13 Fourth MOS transistor

[0046] Q20 Fifth MOS transistor

[0047] Q21 Sixth MOS transistor

[0048] Q30 Seventh MOS transistor

[0049] Q31 Eighth MOS transistor

[0050] R1 Human tissue equivalent resistance

[0051] VDD High potential terminal

[0052] GND Ground terminal

[0053] IO1 First signal input port

[0054] IO2 Second signal input port

[0055] IO3 Third signal input port

[0056] IO4 Fourth signal input port

[0057] IO5 Fifth signal input port

[0058] IO6 Sixth signal input port

[0059] C1 First DC blocking capacitor

[0060] C2 First DC blocking capacitor

[0061] C3 Energy storage capacitor

[0062] I1 Constant current output control module

[0063] R2 First protection resistor

[0064] R3 Second protection resistor

[0065] D1 First diode

[0066] D2 Second diode

[0067] Q31 First triode

[0068] Q32 Second triode

[0069] R4 First anti-leakage resistor

[0070] R5 Second anti-leakage resistor Detailed implementation manners

[0071] The following uses specific specific examples to illustrate the implementation manners of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0072] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner. Therefore, only the components related to the present application are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0073] The following embodiments of the present application provide a channel switching circuit and a stimulator. By means of a unidirectional conduction unit with a conduction direction from the high potential end to the low potential end, the possible parasitic current is blocked, solving the problem in the prior art that the stimulator may generate spurious stimulation electrical signals, causing potential safety hazards.

[0074] The channel switching circuit and the stimulator provided by the following embodiments of the present application include, but are not limited to, being applied to scenarios where, during magnetic resonance imaging (MRI) examinations, induced voltages are generated in the electrode leads in an alternating magnetic field, thereby causing the stimulator to generate spurious stimulation electrical signals on human tissues. The following will describe an example of blocking the parasitic current formed by the induced voltage. It should be noted that the channel switching circuit and the stimulator provided by the following embodiments of the present application can also block parasitic currents that may occur in other application scenarios, and the present application does not make specific limitations here.

[0075] The following will elaborate in detail on the principle and implementation manner of a channel switching circuit and a stimulator according to this embodiment with reference to the accompanying drawings, enabling those skilled in the art to understand the channel switching circuit and the stimulator of this embodiment without creative efforts.

[0076] Specifically, the stimulator described in the present application can be an electrical pulse stimulator, which generates electrical pulses to stimulate human tissues for therapeutic purposes. Of course, it can also be other types of stimulators, and the present application does not make specific limitations here. The following will specifically elaborate with an electrical pulse stimulator as an example.

[0077] Such as Figure 1As shown in the figure, Embodiment 1 of the present invention provides a channel switching circuit 100, including: a high potential terminal VDD, a ground terminal GND, a forward current module, an inverse current module, and an energy storage device connected between the high potential and the low potential. An external output load 115 is connected to the channel switching circuit to form a current loop. The high potential terminal VDD is used to access the working voltage to provide the voltage for forming the electrical stimulation signal. Specifically, the forward current module includes a first forward switch component 111 and a second forward switch component 112, and the inverse current module includes a first inverse switch component 113 and a second inverse switch component 114. The human tissue is connected to the channel switching circuit as the external output load 115, one end is connected to the first forward switch component 111 and the second inverse switch component 114, and the other end is connected to the second forward switch component 112 and the first inverse switch component 113, forming an H-bridge structure. The first forward switch component 111 and the first inverse switch component 113 are connected to the high potential terminal VDD, and the second forward switch component 112 and the second inverse switch component 114 are connected to the ground terminal GND. The first forward switch component 111, the second forward switch component 112, the first inverse switch component 113, and the second inverse switch component 114 are respectively controllably turned on or off to form a forward current path and an inverse current path. Specifically, the first forward switch group 111 is controlled to be turned on or off through the first signal input port IO1, the second forward switch component 112 is controlled to be turned on or off through the third signal input port IO3, the first inverse switch component 113 is controlled to be turned on or off through the fourth signal input port IO4, and the second inverse switch component 114 is controlled to be turned on or off through the second signal input port IO2.

[0078] Exemplarily, the high potential terminal VDD accesses the working voltage. When the first forward switch group 111 and the second forward switch component 112 are turned on, while the first inverse switch component 113 and the second inverse switch component 114 are turned off, the forward current path of the high potential terminal VDD - the first forward switch group 111 - the external output load 115 - the second forward switch component 113 - the ground terminal GND is turned on, generating a forward current stimulation at the equivalent resistance R1 of the human tissue; similarly, when the first inverse switch group 113 and the second inverse switch component 114 are turned on, while the first forward switch component 111 and the second forward switch component 112 are turned off, an inverse current stimulation is generated at the external output load 115. Based on this, by controlling the four switch components of the switching channel circuit, a forward current stimulation or an inverse current stimulation is generated at the external output load 115, thereby achieving the treatment purpose.

[0079] Further, at least one of the first forward switch component 111 and the second forward switch component 112 includes a unidirectional conduction unit, and at least one of the first reverse switch component 113 and the second reverse switch component 114 includes a unidirectional conduction unit. The conduction direction of the unidirectional conduction unit is from the high potential terminal VDD to the ground terminal GND.

[0080] It should be noted that the switch components of the channel switching circuit 100 generally include MOS transistors. Since there are parasitic diodes in the MOS transistors, mis-conduction may occur in the power-off state of the electrical pulse stimulator to form a parasitic current, which may further cause an incorrect stimulation electrical signal at the external output load 115, posing a safety hazard and being unfavorable for the practical application of the electrical pulse stimulator. Specifically, during magnetic resonance imaging (MRI) examination, the electrical pulse stimulator is in a completely powered-off state, that is, the high potential terminal VDD is disconnected. At this time, the electrical pulse stimulator should not generate any electrical signal at the external output load 115. However, in the actual working scenario, since the electrode wire will generate an induced voltage in the alternating magnetic field during MRI examination, this induced voltage will form a parasitic current through the parasitic diode inside the switch component, that is, an incorrect stimulation electrical signal is generated at the external output load 115. As Figure 1As shown, taking the example where the induced voltage generated is at a high potential on the left side of the external output load 115 and at a low potential on the right side, the parasitic diodes of the first forward switch component 111 and the second forward switch component 112 conduct, forming a complete current loop of external output load 115 - parasitic diode of the first forward switch component 111 - energy storage device - parasitic diode of the second forward switch component 112 - external output load 115, and further generating a mis-stimulation electrical signal of reverse current stimulation in the equivalent resistance R1 of the human tissue; similarly, when the induced voltage generated at the external output load 115 is at a high potential on the right side and at a low potential on the left side, a mis-stimulation electrical signal of forward current stimulation will be generated at the external output load 115. And for the unidirectional conduction unit in this embodiment, its conduction direction is from the high potential terminal VDD to the ground terminal GND. Since at least one of the first forward switch component 111 and the second forward switch component 112 includes a unidirectional conduction unit, whose conduction direction is the same as the direction of the forward current path of high potential terminal VDD - first forward switch group 111 - external output load 115 - second forward switch component 113 - ground terminal GND, the normal electrical stimulation signal will not be blocked by the unidirectional conduction unit, and the electrical pulse stimulator can work normally when the operating voltage is connected; while it is opposite to the current loop of external output load 115 - parasitic diode of the first forward switch component 111 - energy storage device - parasitic diode of the second forward switch component 112 - external output load 115, so this current is actually blocked and no mis-stimulation electrical signal will be generated; similarly, since at least one of the first reverse switch component 113 and the second reverse switch component 114 includes a unidirectional conduction unit, it also enables the channel switching circuit 100 to work normally while not generating a mis-stimulation electrical signal of forward current stimulation. Based on this, the channel switching circuit 100 of this embodiment can block the parasitic current while ensuring normal operation, so that the electrical pulse stimulator will not generate mis-stimulation electrical signals, improving the safety of the electrical pulse stimulator.

[0081] Wherein, the power-off state in this application refers to the state where the electrical pulse stimulator is not connected to the operating voltage and the high potential terminal VDD is in an open state.

[0082] In the following, taking the application scenario of nuclear magnetic examination as an example, the working principle and implementation manner of blocking parasitic current in the first embodiment will be specifically described.

[0083] Exemplarily, as Figure 2 shown, the human tissue to be treated is connected to the external output load of the channel switching circuit 100, which is equivalent to the equivalent resistance R1 of the human tissue. The unidirectional conduction unit can be two MOS transistors connected back to back and a protection resistor. One end of the protection resistor is connected to the source electrode of the MOS transistor, and the other end is connected to the gate electrode of the MOS transistor. Exemplarily, as Figure 2As shown, the sources of two MOS transistors are connected, and the unidirectional conduction unit is connected to the circuit through the drains of the two MOS transistors. Here, the channel types of the two MOS transistors are the same. At this time, the conduction directions of the parasitic diodes in the two MOS transistors are opposite. Therefore, when the parasitic diode in one MOS transistor is conductive to the parasitic current, the parasitic diode in the other MOS transistor is cutoff to the parasitic current, thereby blocking the parasitic current.

[0084] Furthermore, the gates of the two back-to-back connected MOS transistors are connected to the same signal input port to synchronously control the on or off states of the two MOS transistors.

[0085] Exemplarily, both the first forward switch component 111 and the first reverse switch component 113 include a unidirectional conduction unit to block the circuit of all parasitic currents. That is, as Figure 2 shown, the first MOS transistor Q10, the fifth MOS transistor Q20, and the first protection resistor R2 in the channel switching circuit 100 form a unidirectional conduction unit. Since the first MOS transistor and the fifth MOS transistor are both controlled by the first signal input port IO1, they are turned on or off synchronously, which does not affect the current flowing from the high potential terminal VDD to the human tissue equivalent resistor R1, that is, it does not affect the generation of the positive current stimulation signal of the electrical pulse stimulator. When performing a nuclear magnetic examination, the electrical pulse stimulator is in a power-off state, and the parasitic diode of the fifth MOS transistor Q20 blocks the current flowing from the human tissue equivalent resistor R1 to the energy storage capacitor C3. That is, the unidirectional conduction unit composed of the first MOS transistor Q10, the fifth MOS transistor Q20, and the first protection resistor R2 only allows the current flowing from the high potential terminal VDD to the ground terminal GND. Similarly, the fourth MOS transistor Q13, the sixth MOS transistor Q21, and the second protection resistor R3 form another unidirectional conduction unit, and only allow the current flowing from the high potential terminal VDD to the ground terminal GND. Based on this, for the channel switching circuit provided in the first embodiment, the forward current path and the reverse current path during normal operation can be conducted as needed. When performing a nuclear magnetic examination, since the parasitic diodes of the fifth MOS transistor Q20 and the sixth MOS transistor Q21 block the current flowing out of the human tissue equivalent resistor R1, the possible parasitic currents are all blocked, ensuring the safety of the electrical pulse stimulator and improving the use effect of the patient.

[0086] It should be noted that for the channel switching circuit 100 provided in the first embodiment, a MOS transistor connected back-to-back is added to one end of the first MOS transistor Q10 close to the high potential end VDD, and a MOS transistor connected back-to-back is added to one end of the fourth MOS transistor Q13 close to the high potential end VDD, so as to block all parasitic currents. In fact, a MOS transistor connected back-to-back can also be added to one end of the first MOS transistor Q10 close to the equivalent resistance R1 of the human tissue, and a MOS transistor connected back-to-back can be added to one end of the fourth MOS transistor Q13 close to the equivalent resistance R1 of the human tissue; or, a MOS transistor connected back-to-back can be added to one end of the second MOS transistor Q11 close to the ground end GND, and a MOS transistor connected back-to-back can be added to one end of the third MOS transistor Q12 close to the ground end GND; or, a MOS transistor connected back-to-back can be added to one end of the second MOS transistor Q11 close to the equivalent resistance R1 of the human tissue, and a MOS transistor connected back-to-back can be added to one end of the second MOS transistor Q11 close to the equivalent resistance R1 of the human tissue close to the equivalent resistance R1 of the human tissue; or, the first MOS transistor Q10 is connected to a MOS transistor connected back-to-back and connected to the circuit, the second MOS transistor Q11 is connected to a MOS transistor connected back-to-back and connected to the circuit, the third MOS transistor Q12 is connected to a MOS transistor connected back-to-back and connected to the circuit, and the fourth MOS transistor Q13 is connected to a MOS transistor connected back-to-back and connected to the circuit. Since the parasitic current loops that generate spurious stimulation electrical signals are actually: the current loop of the equivalent resistance R1 of the human tissue - the parasitic diode of the first MOS transistor Q10 - the energy storage capacitor C3 - the parasitic diode of the third MOS transistor Q12 - the equivalent resistance R1 of the human tissue; and the current loop of the equivalent resistance R1 of the human tissue - the parasitic diode of the fourth MOS transistor Q13 - the energy storage capacitor C3 - the parasitic diode of the second MOS transistor Q11 - the equivalent resistance R1 of the human tissue, as long as a MOS transistor with the conduction direction of the internal parasitic diode opposite to the parasitic current direction is added to the two current loops where spurious stimulation electrical signals may be generated, and the MOS transistor is connected back-to-back with the original MOS transistor in the circuit, the generation of spurious stimulation electrical signals can be blocked. Specifically, it can be set according to the actual needs of the electrical pulse stimulator, and no specific limitation is made here in the first embodiment.

[0087] It should be noted that since the conduction directions of the internal parasitic diodes of the two back-to-back connected MOS transistors in the unidirectional conduction unit are opposite to each other, other possible parasitic currents with different directions are actually blocked. Based on this, the channel switching circuit 100 provided in the first embodiment can block all parasitic currents to avoid generating spurious stimulation electrical signals at the equivalent resistance R1 of the human tissue.

[0088] Preferably, the channel switching circuit 100 provided in the first embodiment further includes a first DC blocking capacitor C1 and a second DC blocking capacitor C2 disposed on both sides of the human tissue equivalent resistance R1, which are used to isolate the parasitic DC bias, avoid the human body polarization effect, and improve the safety of the electrical pulse stimulator.

[0089] Preferably, the channel switching circuit 100 provided in the first embodiment further includes a constant current output control module I1. One end of the constant current output control module I1 is connected to the ground terminal GND, and the other end is connected to the output terminals of both the second forward switch assembly 112 and the second reverse switch assembly 114. Exemplarily, as Figure 2 shown, the constant current output control module I1 is connected to the output terminals of both the second MOS transistor Q11 and the third MOS transistor Q12. The constant current control module I1 is used to stabilize the current intensity of the channel switching circuit 100, and further stabilize the intensities of the forward current stimulation signal and the reverse current stimulation signal, so that the electrical pulse stimulator achieves a better use effect.

[0090] It should be noted that for the channel switching circuit provided in the first embodiment, a voltage difference is formed between the high potential terminal VDD and the ground terminal GND to enable the normal operation of the electrical pulse stimulator. The actual ground terminal GND can adopt other low potential terminals as long as the working conditions of the electrical pulse stimulator can be satisfied. The first embodiment does not make any limitations here.

[0091] Optionally, the energy storage device is an energy storage capacitor C3. Further, the parasitic capacitance of the MOS transistor can equivalently form the energy storage capacitor C3.

[0092] Based on this, for the channel switching circuit 100 provided in the first embodiment, by adding reverse-connected MOS transistors to the loops where parasitic currents may be formed, all loops where parasitic currents may be formed are blocked when the channel switching circuit 100 loses power, thereby avoiding the electrical pulse stimulator from generating mis-stimulating electrical signals on human tissues and improving the safety of the electrical pulse stimulator.

[0093] As Figure 3 shown, the second embodiment provides another channel switching circuit 100. The difference from the previous embodiment is that the channel switching circuit 100 provided in the second embodiment includes a unidirectional conduction unit whose conduction direction is from the high potential terminal VDD to the ground terminal GND. Specifically, the unidirectional conduction unit includes a MOS transistor and a diode connected to the source or drain of the MOS transistor. The conduction direction of the diode is from the high potential terminal VDD to the ground terminal GND.

[0094] It should be noted that since the diode has a one-way conduction property, only the current flowing from the high-potential terminal VDD to the ground terminal GND can pass through, while blocking the current flowing from the human tissue equivalent resistance R1 to the energy storage capacitor C3, thereby being able to block all parasitic currents to avoid generating spurious stimulation electrical signals at the human tissue equivalent resistance R1. For the specific working principle, reference can be made to the foregoing content and will not be elaborated here.

[0095] Exemplarily, both the first forward switch component 111 and the first reverse switch component 113 include a one-way conduction unit to block the circuit of all parasitic currents. As Figure 3 shown, the first MOS transistor Q10 and the first diode D1 form a one-way conduction unit, and the fourth MOS transistor Q13 and the second diode D2 form another one-way conduction unit. Since the conduction directions of the first diode D1 and the second diode D2 are from the high-potential terminal VDD to the ground terminal GND, they will not affect the forward current stimulation signal and the reverse current stimulation signal generated by the electrical pulse stimulator. Therefore, the first diode D1 and the second diode D2 have no influence on the normal operation of the electrical pulse stimulator. When performing a nuclear magnetic examination, the electrical pulse stimulator is in a power-off state, and an induced voltage is generated at the human tissue equivalent resistance R1. The first diode D1 and the second diode D2 block the current flowing out from the human tissue equivalent resistance R1, so that the possible parasitic currents are all blocked, ensuring the safety of the electrical pulse stimulator and improving the use effect of the patient. For the specific working principle, please refer to the foregoing content and will not be elaborated here.

[0096] It should be noted that in the channel switching circuit 100 provided in the second embodiment, a diode with a conduction direction from the high-potential terminal VDD to the ground terminal GND is added to each end of the first MOS transistor Q10 and the fourth MOS transistor Q13 close to the high-potential terminal VDD, so that all parasitic currents are blocked. In fact, as long as a diode is added at other positions on the current loop where spurious stimulation electrical signals may be generated, refer to the first embodiment, and the first embodiment is not specifically limited here.

[0097] Preferably, the diode of the one-way conduction unit is a fast-recovery diode. The fast-recovery diode has a fast switching speed, avoids waveform distortion of the electrical pulse signal, improves the use effect of the electrical pulse stimulator, and has a high breakdown voltage, avoiding reverse leakage current, further enhancing the ability of the one-way conduction unit to block parasitic currents, and improving the effect of shielding spurious stimulation electrical signals of the electrical pulse stimulator.

[0098] The channel switching circuit 100 provided in the second embodiment blocks parasitic currents by adding a diode with a conduction direction from the high-potential terminal VDD to the ground terminal GND on the loop where parasitic currents may be formed, improves the safety of the electrical pulse stimulator, and the circuit is simple and reliable, saving costs.

[0099] As shown Figure 4 in FIG. 3, another channel switching circuit 100 is provided in the third embodiment. The difference from the foregoing embodiment is that the channel switching circuit 100 provided in the third embodiment includes a unidirectional conduction unit whose conduction direction is from the high potential terminal VDD to the ground terminal GND. Specifically, the unidirectional conduction unit includes a triode.

[0100] Specifically, the emitter of the triode is close to the high potential terminal VDD, the collector is close to the ground terminal GND, and the base is connected to the signal input port. It should be noted that when the electrical pulse stimulator is in a power-off state, there is no current in the base of the triode, and the triode is cut off, so parasitic current can be blocked. When the high potential terminal VDD is connected to the working voltage, the triode is controlled to conduct or cut off through the signal input port, thereby forming a forward current stimulation or a reverse current stimulation. Based on this, the triode has no influence on the normal operation of the electrical pulse stimulator, and blocks the parasitic current that may be generated when the electrical pulse stimulator is powered off, ensuring the safety of the electrical pulse stimulator and improving the use effect of the patient.

[0101] It should be noted that one or two MOS transistors in the forward current path are replaced by triodes with the same conduction direction as the original MOS transistors, and one or two MOS transistors in the reverse current path are replaced by triodes with the same conduction direction as the original MOS transistors to block all current loops that may generate parasitic current. Preferably, one MOS transistor in the forward current path is replaced by a triode, and one MOS transistor in the reverse current path is replaced by a triode, that is, the channel switching circuit 100 includes two triodes and two MOS transistors. Since the impedance of the MOS transistor is higher than that of the triode, the generated current signal quality is higher. By setting the channel switching circuit 100 to include two triodes and two MOS transistors, it is possible to avoid the generation of false stimulation electrical signals by the electrical pulse stimulator while ensuring better signal quality and improving the use effect of the electrical pulse stimulator.

[0102] Exemplarily, as shown Figure 4 in FIG. 4, the first triode Q31 serves as a unidirectional conduction unit, and the second triode Q32 serves as another unidirectional conduction unit. When performing a nuclear magnetic examination, the electrical pulse stimulator is in a power-off state, and the first triode Q31 and the second triode Q32 are in a cut-off state, blocking the possible false stimulation electrical signals and ensuring the safety of the electrical pulse stimulator. It should be noted that the third MOS transistor Q12 and the fourth MOS transistor Q13 can also be replaced by triodes to shield the false stimulation electrical signals. Specifically, as long as any MOS transistor on these two current loops that may generate false stimulation electrical signals is replaced by a triode, the generation of false stimulation electrical signals can be blocked. Specifically, it can be set according to the actual needs of the electrical pulse stimulator, and no specific limitation is made in the first embodiment here.

[0103] It should be noted that since the MOS transistor is a voltage-driven device and the triode is a current-driven device, when replacing the MOS transistor with a triode, the circuit structure of the signal input port needs to be changed accordingly. Exemplarily, as Figure 4 shown, the third signal input port IO3 and the fourth signal input port IO4 are voltage-driven circuits, and the fifth signal input port IO5 and the sixth signal input port IO6 are voltage-driven circuits.

[0104] The channel switching circuit 100 provided in the third embodiment can effectively block parasitic current with a simple circuit structure by replacing the MOS transistors required to form the H-bridge circuit with triodes, and can ensure that the electrical pulse stimulator has good signal therapy.

[0105] As Figure 6 shown, the fourth embodiment provides another channel switching circuit 100, which is different from the foregoing embodiments in that the channel switching circuit 100 provided in the fourth embodiment includes a unidirectional conduction unit whose conduction direction is from the high potential end VDD to the ground end GND. Specifically, the unidirectional conduction unit includes a MOS transistor for blocking parasitic current. As Figure 5 shown is the structural schematic diagram of the MOS transistor. Specifically, the MOS transistor includes: a source electrode 101, a drain electrode 102, a gate electrode 103, a substrate 104, and a leakage prevention resistor R6 connected between the source electrode 101 and the substrate 104.

[0106] It should be noted that since the source electrode 101 and the substrate 104 of the MOS transistor are not directly connected together, when the electrical pulse stimulator is in a power-off state, it is equivalent to a diode between the source electrode 101 and the substrate 104, and it is also equivalent to a diode between the drain electrode 102 and the substrate 104. At this time, two diodes with opposite conduction directions are formed inside the MOS transistor, thereby blocking the current. At the same time, when the electrical pulse stimulator is connected to the working voltage, since the source electrode 101 and the substrate 104 are connected through a leakage prevention resistor, the potentials of the source electrode 101 and the substrate 104 are equal, avoiding forward biasing between the source electrode 101 and the substrate 104 and ensuring the normal operation of the MOS transistor. Based on this, the MOS transistor can block parasitic current while achieving normal operation.

[0107] Exemplarily, as Figure 6The source electrode 101 and the substrate 104 of the seventh MOS transistor Q30 shown are connected through a first anti-leakage resistor R4, serving as a one-way conduction unit. The source electrode 101 and the substrate 104 of the eighth MOS transistor Q31 are connected through a second anti-leakage resistor R5, serving as another one-way conduction unit. When the high-potential terminal VDD is connected to the working voltage, all four MOS transistors operate normally to generate a forward current stimulation or a reverse current stimulation at the equivalent human tissue resistance R1 for treatment. When performing a nuclear magnetic examination and the electrical pulse stimulator is in a power-off state, two diodes with opposite conduction directions are formed inside the seventh MOS transistor Q30 and the eighth MOS transistor Q31, blocking all currents, thereby avoiding the generation of false stimulation electrical signals at the equivalent human tissue resistance R1 and improving the safety of the electrical pulse stimulator.

[0108] It should be noted that for the channel switching circuit 100 provided in the fourth embodiment, the seventh MOS transistor Q30 and the eighth MOS transistor Q31 connecting the source electrode 101 and the substrate 104 through anti-leakage resistors block all currents in the power-off state. In fact, the third MOS transistor Q12 and the fourth MOS transistor Q13 can also be set as MOS transistors connecting the source electrode 101 and the substrate 104 through anti-leakage resistors. As long as any ordinary MOS transistor on either of these two current loops where false stimulation electrical signals may be generated is replaced with a MOS transistor connecting the source electrode 101 and the substrate 104 through an anti-leakage resistor, the generation of false stimulation electrical signals can be blocked. Specifically, reference can be made to the foregoing content and set according to the actual needs of the electrical pulse stimulator. No specific limitation is made in the first embodiment here.

[0109] The channel switching circuit 100 provided in the fourth embodiment blocks the parasitic current in the power-off situation through the MOS transistors connecting the source electrode 101 and the substrate 104 with anti-leakage resistors. Moreover, the process is simple, the structure of the channel switching circuit 100 remains unchanged, and no additional devices need to be added, which is beneficial to the miniaturization design of the electrical pulse stimulator.

[0110] As Figures 2 - 4 and Figure 6 shown in the channel switching circuit 100, the one-way conduction units in the same circuit structure are of the same structure. It should be noted that the one-way conduction units in the same circuit structure can also be of different structures. Specifically, it can be designed according to the actual requirements of the electrical pulse stimulator. No specific limitation is made in this application here.

[0111] Furthermore, Embodiment 5 of the present application further provides an electrical pulse stimulator, wherein the channel switching part inside the electrical pulse stimulator is the channel switching circuit 100 as described above. Since the switching component of the channel switching circuit 100 includes a unidirectional conduction unit, when the electrical pulse stimulator loses power, it blocks all possible parasitic current loops, avoiding the generation of mis-stimulating electrical signals, thereby improving the safety of the electrical pulse stimulator and enabling it to work properly when the operating voltage is connected. Specifically, the electrical pulse stimulator can block the current loop of the parasitic current. For its working principle and implementation manner, please refer to the foregoing content and will not be elaborated here.

[0112] In summary, for the channel switching circuit 100 and the stimulator provided by the present application, through the unidirectional conduction unit, when the stimulator is in a power-off state, if the equivalent resistance R1 of the human tissue generates an induced voltage, all possible parasitic diodes generated thereby are blocked, and further the mis-stimulating current is shielded, further improving the safety of the stimulator. At the same time, the unidirectional conduction unit can optionally have various structures; for different unidirectional conduction units in the same channel switching circuit 100, they can be of the same structure or different structures; the channel switching circuit 100 can include two or more unidirectional conduction units. As long as there is at least one unidirectional conduction unit in each current loop where mis-stimulating electrical signals may be generated, the generation of mis-stimulating electrical signals can be blocked. For the channel switching circuit 100 and the stimulator provided by the present application, the specific structure can be determined according to the actual requirements of the stimulator, and the present application does not make specific limitations here.

[0113] The descriptions of the processes or structures corresponding to the above respective drawings have their own emphases. For parts not detailed in a certain process or structure, reference can be made to the relevant descriptions of other processes or structures.

[0114] The above embodiments merely illustrate the principles and effects of the present application, rather than limiting the present application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present application should still be covered by the claims of the present application.

Claims

1. A channel switching circuit, characterized in that: include: A high potential end, a low potential end, a forward current module, a reverse current module and an energy storage device connected between the high potential and the low potential, and an external output load connected to the channel switching circuit to form a current loop; The forward current module and the external output load form a forward current path between the high potential end and the low potential end, and the reverse current module and the external output load form a reverse current path between the high potential end and the low potential end; The forward current module comprises a first forward switch component and a second forward switch component, the first forward switch component, the external output load and the second forward switch component are connected in sequence, and at least one of the first forward switch component and the second forward switch component comprises a unidirectional conduction unit; The reverse current module comprises a first reverse switch component and a second reverse switch component, wherein the first reverse switch component, the external output load and the second reverse switch component are connected in sequence, and at least one of the first reverse switch component and the second reverse switch component comprises a unidirectional conduction unit; The conducting direction of the unidirectional conducting unit is from the high potential end to the low potential end.

2. The channel switching circuit according to claim 1, characterized in that: The unidirectional conductive unit includes two MOS tubes connected back to back and a protection resistor; One end of the protection resistor is connected to the source of the MOS tube, and the other end of the protection resistor is connected to the gate of the MOS tube.

3. The channel switching circuit according to claim 1, characterized in that: The unidirectional conducting unit includes a MOS tube and a diode, and the diode is connected to the source or drain of the MOS tube.

4. The channel switching circuit according to claim 1, characterized in that: The unidirectional conducting unit includes a transistor.

5. The channel switching circuit according to claim 4, characterized in that: At least one of the first forward switch component and the second forward switch component includes a MOS transistor; at least one of the first reverse switch component and the second reverse switch component includes a MOS transistor.

6. The channel switching circuit according to claim 1, characterized in that: The unidirectional conducting unit comprises a MOS tube and an anti-leakage resistor, and two ends of the anti-leakage resistor are respectively connected to the source and substrate of the MOS tube.

7. The channel switching circuit according to claim 1, characterized in that: It also includes two DC blocking capacitors respectively located at two sides of the external output load.

8. The channel switching circuit according to claim 1, characterized in that: It also includes a constant current output control module, one end of which is connected to the low potential end, and the other end of which is connected to the output ends of the second forward switch component and the second reverse switch component.

9. The channel switching circuit according to claim 1, characterized in that: The low potential end is a ground end.

10. A stimulator, characterized in that: The channel switching part inside the stimulator is a channel switching circuit as described in any one of claims 1-9.

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